Ask anyone who's moved from Japan about San Francisco's izakaya boom and they'll roll their eyes, agreeing with you that all it seems to take to call yourself an izakaya here is to add a few skewers to your sushi menu. And then they'll interrupt the complaining to interject, Except Ippuku, of course. Christian Geideman's restaurant — brutishly beautiful, serenely industrial — is the product of a focus so intense it's almost, well, Japanese. He specializes in chicken in many guises, from grilled swaths of skin to turnips braised with ground meat, but the menu's broad enough to include beef tartare, fresh sea urchin, and avocado sashimi. And like a proper izakaya, Ippuku is a place for drinking, stocking one of the largest collections of shochu in the state, and craft beers on tap, to boot.